Golfers need golf clubs that can be used to hit the ball the right distance in the intended direction and enjoy the game more when the golf clubs have been customized and personalized to match their abilities and preferences. Over the last ten years, golf club manufacturers have made many attempts to offer golfers the ability to adjust and customize their golf clubs. Some attempts include adjustable weight systems, adjustable loft or lie angles, means to attenuate sound, and personalization. Those clubs are fraught with problems because the adjustment mechanisms interfere with aerodynamics, collect dirt and grime, have small parts that break when they hit the ground during use, and are difficult to use. Some attempts have been made to put weights inside of golf clubs. For example, U.S. Pub. 2008/0261715 to Carter shows a golf club head with tracks and weights. U.S. Pat. No. 8,206,243 to Stites reports a movable weight member in a golf club head. U.S. Pub. 2013/0260913 to Beach shows a club head with a track with a weight. U.S. Pub. 2013/0296070 to Stites shows a club head with face-aft weight slot in the sole. Unfortunately, some weight systems break during use. External adjustment mechanisms are complicated to use, fragile, and adversely affect inertial properties.